The present disclosure relates to a light emitting device, a light emitting device package, and a lighting system.
Light Emitting Diodes (LEDs) are frequently used as the light emitting device.
The LEDs are a semiconductor light emitting device which transforms electric current into light.
Wavelengths of light emitted from such LEDs vary according to semiconductor materials used in manufacturing the LEDs. This is so since the wavelengths of the emitted light vary according to band-gaps of the semiconductor materials representing energy differences between valence band electrons and conduction band electrons.
Brightness of the LEDs has been gradually increased such that the LEDs are used as light sources for displays, automobiles, and lighting, and it is possible to realize LEDs emitting white light with excellent efficiency by using phosphor or combining LEDs of various colors.